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Differential static system

By including this new variable in the differential equation system (2.107) and in the initial and limiting conditions, these are transformed into a one-variable problem (.v )MKj of identical form to that given by Eqs. (2.9)-(2.12) for static planar electrodes that is, c0 and cR can be expressed as functions of only one variable, SqME and srme, respectively. Thus, by following the same procedure indicated by Eqs. (2.13)—(2.18), one obtains expressions for the concentration profiles ... [Pg.97]

There is a bewildering amount of information on the kinetics of ethylene oxidation over silver. Static, flow, differential, and recycle systems have been used with various catalysts, feed ratios, and additives. From this work two conclusions are clear (1) it is not possible to cover all conditions with a simple rate law and (2) attempts to determine mechanisms by means of kinetics are quite risky. Earlier studies have been reviewed by Margolis (f), Sampson and Shooter (2), and Dixon and Longfield (S7). The classic paper was that of Twigg (34), who used mainly a static system. By now it is evident that, although Twigg s results contain much of value, they are not directly applicable to flow systems using modem catalysts. Under practical conditions the... [Pg.163]

Figure 10 Simon and Knobler s static system for low temperatures. A, filling tube, B, differential pressure transducer, C, coil D, thermostatted bulb E, valve F, gas burette system G, mercury manometer (Reproduced by permission from /. Chem. Thermodynamics, 1971, 3, 657)... Figure 10 Simon and Knobler s static system for low temperatures. A, filling tube, B, differential pressure transducer, C, coil D, thermostatted bulb E, valve F, gas burette system G, mercury manometer (Reproduced by permission from /. Chem. Thermodynamics, 1971, 3, 657)...
The numerical solution is performed by the method of lines. Spatial discretization of the partial differential-equation system using finite differences on statically adapted grids leads to large systems of ordinary differential and algebraic equations. This system of coupled equations is solved by an implicit extrapolation method using the software package LIMEX [14]. The code computes species mass-fraction and temperature profiles in the gas phase, fluxes at the gas-surface interface, and surface temperature and coverage as function of time. [Pg.268]

For a static equilibrium problem the partial differential equation system in Eulerian form together with the boundary conditions is given by... [Pg.33]

Balancing of manifolded systems is often very difficult. The use of damper within the system was the generally accepted method until fairly recently. The use of dampers has not proven to be effective because they tend to fail for a variety of reasons and are difficult to keep adjusted. More recently, balancing of manifolded systems has been accomplished by use of static pressure differentials. This method has proved to be very effective, but has limitations. [Pg.228]

Our model consists of the four ordinary differential equations (7.189) to (7.192) in the dynamics case and of the corresponding set of coupled rational equations in the static case. These two sets of equations can be solved and studied via MATLAB in order to find the system s steady states, the fermentor s dynamic behavior and to control it. [Pg.520]

The difference between the pump discharge pressure curve and the system curve (which is the sum of the static head and the pipe friction loss) is the available valve differential. [Pg.212]

Henri de Pitot invented the Pitot tube in 1732. It is a small, open-ended tube that is inserted into the process pipe with its open end facing into the flow. The differential between the total pressure on this open impact port and the static pipeline pressure is measured as an indication of the flow. The Pitot tubes provide a low-cost measurement with negligible pressure loss and can also be inserted into the process pipes while the system is under pressure (wet- or hot-tapping). They are also used for temporary measurements and for the determination of velocity profiles by traversing pipes and ducts. [Pg.420]

Epithelial cells are interconnected at the apical (mucosal) side by a complex network of proteins, called the tight junctions (TJ). First thought to have merely a static role in restricting access of compounds present in the luminal fluid to the underlying subepithelial tissue and systemic circulation by the paracellular pathway, TJ are known today to be dynamic structures involved in cellular differentiation, cell signaling (Harder and Margolis 2008), polarized vesicle trafficking, and protein synthesis. [Pg.57]

The term chemisorption was coined in order to classify the interaction between a particle in the gas phase and a solid surface, i.e. the result of the adsorption process [1]. If the interaction leads to the formation of a chemical bond the adsorbate formed is called a chem-isorbate. Where chemical bond formation is not important the process is classified as physisorption. There are several conceptual problems with such a differentiation which we briefly address in the following, and which indicate that a more detailed look at the entire process of adsorbate formation is needed before a reliable classification may be carried out. In fact, as it turns out, for a conclusive classification one would need the full theoretical and experimental understanding of the system under investigation. Such an approach must include the static aspects, i.e. the energies involved, as well as the dynamic aspects, i.e. the processes involved in the formation of the adsorptive interactions. [Pg.273]

The coefficients that appear in this expansion describe the response of the molecular system to the external perturbation x and are known as molecular properties. The molecular properties are characteristic of the molecular system and its quantum state. When the perturbation is static, these properties may be calculated by differentiation at x = 0... [Pg.149]

All macroscopic aspects of the statics and dynamics of electromagnetic field in the presence of material media are described by Maxwell s equations. The differential form of these axioms in the International System of Units (SI) or rationalized MKS system (Cohen and Giacomo, 1987 Lide, 1991) is given in... [Pg.125]


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See also in sourсe #XX -- [ Pg.14 , Pg.15 ]




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